From 47999efebecb05d1a4c9e2c29244b5a37ee43b62 Mon Sep 17 00:00:00 2001
From: Natasa Kasikovic~ <nkasikovic@yahoo.com>
Date: Sun, 28 Apr 2024 14:43:07 +0200
Subject: [PATCH 1/9] [Refactor]: ExamSlot is no longer dependent on a specific
 course instance

---
 LangLang/Core/Model/ExamSlot.cs    | 114 ++++++++---------------------
 LangLang/Core/Model/Overlapable.cs |   8 ++
 LangLang/Core/Model/TimeSlot.cs    |  26 +++++++
 3 files changed, 66 insertions(+), 82 deletions(-)
 create mode 100644 LangLang/Core/Model/Overlapable.cs
 create mode 100644 LangLang/Core/Model/TimeSlot.cs

diff --git a/LangLang/Core/Model/ExamSlot.cs b/LangLang/Core/Model/ExamSlot.cs
index 436f202a..aae1ba7e 100644
--- a/LangLang/Core/Model/ExamSlot.cs
+++ b/LangLang/Core/Model/ExamSlot.cs
@@ -1,104 +1,54 @@
 using LangLang.Core.Repository.Serialization;
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 
 namespace LangLang.Core.Model
 {
-    public class ExamSlot: ISerializable
+    public class ExamSlot: ISerializable, Overlapable
     {
-        // Private attributes
-        private int _id;
-        private int _courseId;
-        private int _maxStudents;
-        private DateTime _examDateTime;
-        private int _numberOfStudents;
+        public int Id { get; set; }
+        public string Language { get; set; }
+        public LanguageLevel Level { get; set; }
+        
+        public int TutorId { get; set; }
 
-        // Public properties
-        public int Id
-        {
-            get { return _id; }
-            set { _id = value; }
-        }
+        public TimeSlot TimeSlot { get; set; }
+        public int MaxStudents { get; set; }
 
-        public int CourseId
-        {
-            get { return _courseId; }
-            set { _courseId = value; }
-        }
+        // NOTE: if possible don't save number of registeredStudents, ask the database. If not, then add attribute.
+        
 
-        public int MaxStudents
+        public ExamSlot(int id, string language, LanguageLevel level, TimeSlot timeSlot, int maxStudents, int tutorId)
         {
-            get { return _maxStudents; }
-            set { _maxStudents = value; }
-        }
-
-        public DateTime ExamDateTime
-        {
-            get { return _examDateTime; }
-            set { _examDateTime = value; }
-        }
-
-        public int NumberOfStudents
-        {
-            get { return _numberOfStudents; }
-            set { _numberOfStudents = value; }
-        }
-
-        // Constructor
-        public ExamSlot(int id, int courseId, int maxStudents, DateTime examDateTime, int numberOfStudents)
-        {
-            _id = id;
-            _courseId = courseId;
-            _maxStudents = maxStudents;
-            _examDateTime = examDateTime;
-            _numberOfStudents = numberOfStudents;
-        }
-
-        public ExamSlot(int id, int courseId, int maxStudents, DateTime examDateTime)
-        {
-            _id = id;
-            _courseId = courseId;
-            _maxStudents = maxStudents;
-            _examDateTime = examDateTime;
-            _numberOfStudents = 0;
+            Id = id;
+            Language = language;
+            Level = Level;
+            TutorId = tutorId;
+            TimeSlot = timeSlot;
+            MaxStudents = maxStudents;
         }
 
         public ExamSlot() { }
 
-        // Methods
-
-        // Method to display information about the exam slot
-        public override string ToString()
-        {
-            return $"ID: {_id} | Course: {_courseId.ToString()} | Max Students: {_maxStudents} | Exam Date and Time: {_examDateTime} | Number of Students: {_numberOfStudents}";
-        }
-
-        // Method to convert object to CSV format
-        //returns array of strings representing attributes of ExamSlot object in string form
         public string[] ToCSV()
         {
-            string[] csvValues =
-            {
-            _id.ToString(),
-            _courseId.ToString(),
-            _maxStudents.ToString(),
-            _examDateTime.ToString(),
-            _numberOfStudents.ToString()
-        };
-            return csvValues;
+            return new string[] {
+            Id.ToString(),
+            Language,
+            Level.ToString(),
+            TutorId.ToString(),
+            // TODO: add serialization for timeSlot when implemented
+            MaxStudents.ToString(),
+            };
         }
-        // Method to make object from CSV data
-        //takes array of strings representing ExamSlot object values and sets attributes of object to that values
+
         public void FromCSV(string[] values)
         {
-            _id = int.Parse(values[0]);
-            _courseId = int.Parse(values[1]);
-            _maxStudents = int.Parse(values[2]);
-            _examDateTime = DateTime.Parse(values[3]);
-            _numberOfStudents = int.Parse(values[4]);
+            Id = int.Parse(values[0]);
+            Language = values[1];
+            Level = (LanguageLevel)Enum.Parse(typeof(LanguageLevel), values[2]);
+            TutorId = int.Parse(values[3]);
+            // TODO: add deserialization for timeSlot when implemented
+            MaxStudents = int.Parse(values[6]);
         }
     }
 }
diff --git a/LangLang/Core/Model/Overlapable.cs b/LangLang/Core/Model/Overlapable.cs
new file mode 100644
index 00000000..96a19ac1
--- /dev/null
+++ b/LangLang/Core/Model/Overlapable.cs
@@ -0,0 +1,8 @@
+
+namespace LangLang.Core.Model
+{
+    public interface Overlapable
+    {
+        // TODO: implement
+    }
+}
diff --git a/LangLang/Core/Model/TimeSlot.cs b/LangLang/Core/Model/TimeSlot.cs
new file mode 100644
index 00000000..2073b029
--- /dev/null
+++ b/LangLang/Core/Model/TimeSlot.cs
@@ -0,0 +1,26 @@
+using System;
+using System.Runtime.Serialization;
+
+namespace LangLang.Core.Model
+{
+    public class TimeSlot
+    {
+        // NOTE: Adapt as needed during implementation
+        public int Duration { get; set; }
+        public DateTime time { get; set; }
+
+        public bool OverlappsWith(TimeSlot timeSlot)
+        {
+            // TODO: Implement
+            return false;
+        }
+
+        public bool IsInFuture()
+        {
+            // TODO: Implement
+            return false;
+        }
+
+        // TODO: Add serialization methods
+    }
+}

From 9004a4475e1722d0b89201d62663fad71c3b798a Mon Sep 17 00:00:00 2001
From: Natasa Kasikovic~ <nkasikovic@yahoo.com>
Date: Sun, 28 Apr 2024 16:36:38 +0200
Subject: [PATCH 2/9] [Add] an attribute indicating whether exam registration
 is possible

---
 LangLang/Core/Model/ExamSlot.cs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/LangLang/Core/Model/ExamSlot.cs b/LangLang/Core/Model/ExamSlot.cs
index aae1ba7e..c7e31314 100644
--- a/LangLang/Core/Model/ExamSlot.cs
+++ b/LangLang/Core/Model/ExamSlot.cs
@@ -8,16 +8,15 @@ public class ExamSlot: ISerializable, Overlapable
         public int Id { get; set; }
         public string Language { get; set; }
         public LanguageLevel Level { get; set; }
-        
         public int TutorId { get; set; }
-
         public TimeSlot TimeSlot { get; set; }
         public int MaxStudents { get; set; }
+        public bool ApplicationPossible { get; set; }
 
         // NOTE: if possible don't save number of registeredStudents, ask the database. If not, then add attribute.
         
 
-        public ExamSlot(int id, string language, LanguageLevel level, TimeSlot timeSlot, int maxStudents, int tutorId)
+        public ExamSlot(int id, string language, LanguageLevel level, TimeSlot timeSlot, int maxStudents, int tutorId, bool applicationPossible)
         {
             Id = id;
             Language = language;
@@ -25,6 +24,7 @@ public ExamSlot(int id, string language, LanguageLevel level, TimeSlot timeSlot,
             TutorId = tutorId;
             TimeSlot = timeSlot;
             MaxStudents = maxStudents;
+            ApplicationPossible = applicationPossible;
         }
 
         public ExamSlot() { }
@@ -38,6 +38,7 @@ public string[] ToCSV()
             TutorId.ToString(),
             // TODO: add serialization for timeSlot when implemented
             MaxStudents.ToString(),
+            ApplicationPossible.ToString()
             };
         }
 
@@ -49,6 +50,7 @@ public void FromCSV(string[] values)
             TutorId = int.Parse(values[3]);
             // TODO: add deserialization for timeSlot when implemented
             MaxStudents = int.Parse(values[6]);
+            ApplicationPossible = bool.Parse(values[7]);
         }
     }
 }

From de75c42a5f02e07778ecf7e8c5ad3f882e7cf0b6 Mon Sep 17 00:00:00 2001
From: Darinka Loncar <149894872+darinkaloncar@users.noreply.github.com>
Date: Sun, 28 Apr 2024 13:18:53 -0700
Subject: [PATCH 3/9] [Update] CourseDTO class

Code clean up
---
 LangLang/DTO/CourseDTO.cs                     | 122 +++++-------------
 .../View/CourseGUI/CourseCreateWindow.xaml    |   2 +-
 .../View/CourseGUI/CourseUpdateWindow.xaml    |   2 +-
 3 files changed, 31 insertions(+), 95 deletions(-)

diff --git a/LangLang/DTO/CourseDTO.cs b/LangLang/DTO/CourseDTO.cs
index a12c5d9b..fb050808 100644
--- a/LangLang/DTO/CourseDTO.cs
+++ b/LangLang/DTO/CourseDTO.cs
@@ -25,7 +25,7 @@ public class CourseDTO : INotifyPropertyChanged, IDataErrorInfo
         private List<DayOfWeek> days;
         private bool online;
         private int maxStudents;
-        private DateTime startDateTime;
+        private DateTime startDate;
         private bool createdByDirector;
         private string time;
         private bool mon;
@@ -143,18 +143,18 @@ public string Time
             }
         }
 
-        public DateTime StartDateTime
+        public DateTime StartDate
         {
             get
             {
-                return startDateTime;
+                return startDate;
             }
             set
             {
-                if (value != startDateTime)
+                if (value != startDate)
                 {
-                    startDateTime = value;
-                    OnPropertyChanged("StartDateTime");
+                    startDate = value;
+                    OnPropertyChanged("StartDate");
                 }
             }
         }
@@ -294,10 +294,10 @@ public string this[string columnName]
                     if (timeParts.Length != 2) return "Time format must be HH:mm";
                     else return "";
                 }
-                if (columnName == "StartDateTime")
+                if (columnName == "StartDate")
                 {
-                    if (startDateTime < DateTime.Now) return "Please enter a valid date. Dates in the past are not allowed.";
-                    if (startDateTime == default) return "Birth date is required";
+                    if (startDate < DateTime.Now) return "Please enter a valid date. Dates in the past are not allowed.";
+                    if (startDate == default) return "Birth date is required";
                     else return "";
                 }
                 if (columnName == "NumberOfWeeks")
@@ -313,19 +313,21 @@ public string this[string columnName]
                 return "";
             }
         }
+
+        private string[] _validatedProperties = {"StartDate", "Language", "Level", "NumberOfWeeks", "Time" };
+
         public string ConcatenatedDays
         {
             get { return string.Join(", ", Days); }
         }
 
-        private string[] _validatedProperties = { "StartDateTime", "Language", "Level", "NumberOfWeeks", "Time" };
-
         // checks if all properties are valid
         public bool IsValid
         {
             get
             {
-                if (online == false)
+                // if the course is held in person add validation for maximal number of student, otherwize remove it
+                if (online == false) 
                 {
                     _validatedProperties = _validatedProperties.Append("MaxStudents").ToArray();
                 }
@@ -345,37 +347,22 @@ public bool IsValid
                         _validatedProperties = newArray;
                     }
                 }
-                days = new List<DayOfWeek>();
-                if (mon)
-                {
-                    days.Add(DayOfWeek.Monday);
-                }
-                if (tue)
-                {
-                    days.Add(DayOfWeek.Tuesday);
-                }
-                if (wed)
-                {
-                    days.Add(DayOfWeek.Wednesday);
-                }
-                if (thu)
-                {
-                    days.Add(DayOfWeek.Thursday);
-                }
-                if (fri)
-                {
-                    days.Add(DayOfWeek.Friday);
-                }
-                if (days.Count == 0)
-                {
-                    return false;
-                }
+
                 foreach (var property in _validatedProperties)
                 {
-                    if (this[property] != "")
-                        return false;
+                    if (this[property] != "") return false;
                 }
 
+                List<DayOfWeek> _days = new List<DayOfWeek>();
+
+                if (mon) _days.Add(DayOfWeek.Monday);
+                if (tue) _days.Add(DayOfWeek.Tuesday);
+                if (wed) _days.Add(DayOfWeek.Wednesday);
+                if (thu) _days.Add(DayOfWeek.Thursday);
+                if (fri) _days.Add(DayOfWeek.Friday);
+
+                if(_days.Count == 0) return false;
+                days = _days;
                 return true;
             }
         }
@@ -399,7 +386,7 @@ public Course ToCourse()
             string[] timeParts = time.Split(':');
             int hour = int.Parse(timeParts[0]);
             int minute = int.Parse(timeParts[1]);
-            return new Course(Id, tutorId, language, level, numberOfWeeks, days, online, maxStudents, new DateTime(startDateTime.Year, startDateTime.Month, startDateTime.Day, hour, minute, 0), createdByDirector);
+            return new Course(Id, tutorId, language, level, numberOfWeeks, days, online, maxStudents, new DateTime(startDate.Year, startDate.Month, startDate.Day, hour, minute, 0), createdByDirector);
         }
 
         public CourseDTO(Course course)
@@ -412,59 +399,8 @@ public CourseDTO(Course course)
             TutorId = course.TutorId;
             Days = course.Days;
             NumberOfStudents = course.NumberOfStudents;
-            StringBuilder sbDays = new StringBuilder(); 
-            if (Days.Contains(DayOfWeek.Monday))
-            {
-                Mon = true;
-                sbDays.Append("Mon ");
-            }
-            else
-            {
-                Mon = false;
-            }
-            if (Days.Contains(DayOfWeek.Tuesday))
-            {
-                Tue = true;
-                sbDays.Append("Tue ");
-            }
-            else
-            {
-                Tue = false;
-            }
-            if (Days.Contains(DayOfWeek.Wednesday))
-            {
-                Wed = true;
-                sbDays.Append("Wed ");
-            }
-            else
-            {
-                Wed = false;
-            }
-            if (Days.Contains(DayOfWeek.Thursday))
-            {
-                Thu = true;
-                sbDays.Append("Thu ");
-            }
-            else
-            {
-                Thu = false;
-            }
-            if (Days.Contains(DayOfWeek.Friday))
-            {
-                Fri = true;
-                sbDays.Append("Fri ");
-            }
-            else
-            {
-                Fri = false;
-            }
-            // Deletes the last white space from stringbuilder
-            if (sbDays.Length > 0)
-            {
-                sbDays.Remove(sbDays.Length - 1, 1);
-            }
-            StringDays = sbDays.ToString();
-            StartDateTime = course.StartDateTime;
+            StringDays = ConcatenatedDays;
+            StartDate = course.StartDateTime;
             NumberOfWeeks = course.NumberOfWeeks.ToString();
             MaxStudents = course.MaxStudents.ToString();
             Time = course.StartDateTime.ToString("HH:mm");
diff --git a/LangLang/View/CourseGUI/CourseCreateWindow.xaml b/LangLang/View/CourseGUI/CourseCreateWindow.xaml
index e7635ed8..13dbf5d4 100644
--- a/LangLang/View/CourseGUI/CourseCreateWindow.xaml
+++ b/LangLang/View/CourseGUI/CourseCreateWindow.xaml
@@ -206,7 +206,7 @@
                 </Label.Background>
             </Label>
             <DatePicker Margin="5,0,5,0" x:Name="startDateDp" Background="#FFFFDDDD"
-             SelectedDate="{Binding Path=Course.StartDateTime, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True, StringFormat={}{0:MM/dd/yyyy}}"
+             SelectedDate="{Binding Path=Course.StartDate, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True, StringFormat={}{0:MM/dd/yyyy}}"
              Validation.ErrorTemplate="{StaticResource ValidationTemplate}" Grid.ColumnSpan="2" />
 
             <Label Margin="5,20,5,0" x:Name="classTimeLbl" Content="Class time" FontStyle="Italic" Foreground="Black" RenderTransformOrigin="0.5,0.5" FontFamily="Arial" FontWeight="Bold">
diff --git a/LangLang/View/CourseGUI/CourseUpdateWindow.xaml b/LangLang/View/CourseGUI/CourseUpdateWindow.xaml
index e0c0c9e5..e12933a8 100644
--- a/LangLang/View/CourseGUI/CourseUpdateWindow.xaml
+++ b/LangLang/View/CourseGUI/CourseUpdateWindow.xaml
@@ -206,7 +206,7 @@
                 </Label.Background>
             </Label>
             <DatePicker Margin="5,0,5,0" x:Name="startDateDp" Background="#FFFFDDDD"
-         SelectedDate="{Binding Path=Course.StartDateTime, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}"
+         SelectedDate="{Binding Path=Course.StartDate, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}"
          Validation.ErrorTemplate="{StaticResource ValidationTemplate}" Grid.ColumnSpan="2" />
 
             <Label Margin="5,20,5,0" x:Name="classTimeLbl" Content="Class time" FontStyle="Italic" Foreground="Black" RenderTransformOrigin="0.5,0.5" FontFamily="Arial" FontWeight="Bold">

From 4d44af9f0959e1a781da48a88a9a1cca71407e43 Mon Sep 17 00:00:00 2001
From: Darinka Loncar <149894872+darinkaloncar@users.noreply.github.com>
Date: Sun, 28 Apr 2024 13:34:41 -0700
Subject: [PATCH 4/9] [Update] CourseTable_SelectionChanged function

---
 LangLang/View/TutorWindow.xaml    |  2 +-
 LangLang/View/TutorWindow.xaml.cs | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/LangLang/View/TutorWindow.xaml b/LangLang/View/TutorWindow.xaml
index afcaab17..0d6540d2 100644
--- a/LangLang/View/TutorWindow.xaml
+++ b/LangLang/View/TutorWindow.xaml
@@ -45,7 +45,7 @@
                 </StackPanel>
 
                 <!--table for courses-->
-                <DataGrid  EnableRowVirtualization="False" CanUserAddRows="False"  AutoGenerateColumns="False" x:Name="coursesTable" Margin="15,45,15,0" SelectedItem="{Binding SelectedCourse, UpdateSourceTrigger=PropertyChanged}" SelectionChanged="coursesTable_SelectionChanged">
+                <DataGrid  EnableRowVirtualization="False" CanUserAddRows="False"  AutoGenerateColumns="False" x:Name="coursesTable" Margin="15,45,15,0" SelectedItem="{Binding SelectedCourse, UpdateSourceTrigger=PropertyChanged}" SelectionChanged="CoursesTable_SelectionChanged">
                     <DataGrid.Columns>
                         <DataGridTextColumn x:Name="idColumn" IsReadOnly="True" Header="Id" Binding="{Binding Id}"/>
                         <DataGridTextColumn IsReadOnly="True" Header="Language" Binding="{Binding Language}"/>
diff --git a/LangLang/View/TutorWindow.xaml.cs b/LangLang/View/TutorWindow.xaml.cs
index f2ab4eee..6e1bbc83 100644
--- a/LangLang/View/TutorWindow.xaml.cs
+++ b/LangLang/View/TutorWindow.xaml.cs
@@ -178,7 +178,25 @@ private void CourseDeleteBtn_Click(object sender, RoutedEventArgs e)
                 MessageBox.Show("Selected course cannot be deleted, it has already started or there are less than 7 days before course start.");
             }
         }
-        private void coursesTable_SelectionChanged(object sender, SelectionChangedEventArgs e)
+
+        private void CoursesTable_SelectionChanged(object sender, SelectionChangedEventArgs e)
+        {
+            if (SelectedCourse == null)
+            {
+                disableButtonsCourse();
+            }
+            else
+            {
+                enableButtonsCourse();
+            }
+        }
+
+        private void disableButtonsCourse()
+        {
+            courseUpdateBtn.IsEnabled = false;
+            courseDeleteBtn.IsEnabled = false;
+        }
+        private void enableButtonsCourse()
         {
             courseUpdateBtn.IsEnabled = true;
             courseDeleteBtn.IsEnabled = true;

From 5131f7676a67af066d4b9f34fd3d37760f4f9412 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ana=20=C5=A0inik?= <sinikana7@gmail.com>
Date: Mon, 29 Apr 2024 10:09:13 +0200
Subject: [PATCH 5/9] [feat] Refine handling of student course enrollment
 requests

---
 .../Controller/EnrollmentRequestController.cs | 24 ++++++--
 LangLang/Core/Controller/StudentController.cs | 11 +++-
 .../Core/Model/DAO/EnrollmentRequestDAO.cs    | 60 +++++++++++++++----
 LangLang/Core/Model/DAO/StudentDAO.cs         | 35 +++++++----
 LangLang/Core/Model/EnrollmentRequest.cs      | 19 ++++--
 LangLang/Core/Model/Enums/Status.cs           |  3 +-
 LangLang/Data/enrollmentRequests.csv          | 12 ++--
 LangLang/Data/students.csv                    |  2 +-
 .../View/StudentGUI/StudentWindow.xaml.cs     |  2 +-
 9 files changed, 124 insertions(+), 44 deletions(-)

diff --git a/LangLang/Core/Controller/EnrollmentRequestController.cs b/LangLang/Core/Controller/EnrollmentRequestController.cs
index c48674df..a40f2c78 100644
--- a/LangLang/Core/Controller/EnrollmentRequestController.cs
+++ b/LangLang/Core/Controller/EnrollmentRequestController.cs
@@ -1,9 +1,7 @@
-
-using LangLang.Core.Model.DAO;
+using LangLang.Core.Model.DAO;
 using System.Collections.Generic;
 using LangLang.Core.Model;
 using LangLang.Core.Observer;
-using System.Linq;
 
 namespace LangLang.Core.Controller
 {
@@ -16,7 +14,7 @@ public EnrollmentRequestController()
             _enrollmentRequests = new EnrollmentRequestDAO();
         }
 
-        public Dictionary<int, EnrollmentRequest> GetAll()
+        public List<EnrollmentRequest> GetAll()
         {
             return _enrollmentRequests.GetAllEnrollmentRequests();
         }
@@ -45,5 +43,23 @@ public List<EnrollmentRequest> GetStudentRequests(int studentId)
         {
             return _enrollmentRequests.GetStudentRequests(studentId);
         }
+
+        public bool CancelRequest(EnrollmentRequest enrollmentRequest, CourseController courseController)
+        {
+            Course course = courseController.GetById(enrollmentRequest.CourseId);
+            return _enrollmentRequests.CancelRequest(enrollmentRequest, course);
+        }
+
+        // this method is invoked when the tutor approves the request for the student
+        public void PauseRequests(int studentId, EnrollmentRequest enrollmentRequest)
+        {
+            _enrollmentRequests.PauseRequests(studentId, enrollmentRequest.Id);
+        }
+
+        // this method is invoked when the student complete/withdrawal_from course
+        public void ResumePausedRequests(int studentId)
+        {
+            _enrollmentRequests.ResumePausedRequests(studentId);
+        }
     }
 }
\ No newline at end of file
diff --git a/LangLang/Core/Controller/StudentController.cs b/LangLang/Core/Controller/StudentController.cs
index 798e34e6..f6a43fdb 100644
--- a/LangLang/Core/Controller/StudentController.cs
+++ b/LangLang/Core/Controller/StudentController.cs
@@ -41,7 +41,6 @@ public void Subscribe(IObserver observer)
             _students.Subscribe(observer);
         }
 
-
         public List<Course> GetAvailableCourses(CourseController courseController) 
         {
             return _students.GetAvailableCourses(courseController);
@@ -52,9 +51,14 @@ public List<ExamSlot> GetAvailableExamSlots(Student student, CourseController co
             return _students.GetAvailableExamSlots(student, courseController, examSlotController, enrollmentRequestController);
         }
 
-        public bool CanModifyInfo(int studentId, EnrollmentRequestController erc)
+        public bool CanModifyInfo(int studentId, EnrollmentRequestController erController, CourseController courseController)
         {
-            return _students.CanModifyInfo(studentId, erc);
+            return _students.CanModifyInfo(studentId, erController, courseController);
+        }
+
+        public bool CanRequestEnroll(int id, EnrollmentRequestController erController, CourseController courseController)
+        {
+            return _students.CanRequestEnroll(id, erController, courseController);
         }
 
         public List<ExamSlot> SearchExamSlotsByStudent(ExamSlotController examSlotController, CourseController courseController, EnrollmentRequestController enrollmentRequestController, int studentId, DateTime examDate, string courseLanguage, LanguageLevel? languageLevel)
@@ -69,5 +73,6 @@ public List<Course> SearchCoursesByStudent(CourseController courseController, st
             List<Course> filteredCourses = courseController.SearchCourses(availableCourses, language, level, startDate, duration, online);
             return filteredCourses;
         }
+
     }
 }
diff --git a/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs b/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs
index cf26c45a..403bb8eb 100644
--- a/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs
+++ b/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs
@@ -1,5 +1,7 @@
-using LangLang.Core.Observer;
+using LangLang.Core.Model.Enums;
+using LangLang.Core.Observer;
 using LangLang.Core.Repository;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 
@@ -18,7 +20,7 @@ public EnrollmentRequestDAO()
         private int GenerateId()
         {
             if (_enrollmentRequests.Count == 0) return 0;
-            return _enrollmentRequests.Count + 1;
+            return _enrollmentRequests.Keys.Max() + 1;
         }
 
         public EnrollmentRequest? GetEnrollmentRequestById(int id)
@@ -26,9 +28,9 @@ private int GenerateId()
             return _enrollmentRequests[id];
         }
 
-        public Dictionary<int, EnrollmentRequest> GetAllEnrollmentRequests()
+        public List<EnrollmentRequest> GetAllEnrollmentRequests()
         {
-            return _enrollmentRequests;
+            return _enrollmentRequests.Values.ToList();
         }
 
         public EnrollmentRequest Add(EnrollmentRequest enrollmentRequest)
@@ -42,11 +44,12 @@ public EnrollmentRequest Add(EnrollmentRequest enrollmentRequest)
 
         public EnrollmentRequest? Update(EnrollmentRequest enrollmentRequest)
         {
-            EnrollmentRequest oldRequest = GetEnrollmentRequestById(enrollmentRequest.Id);
+            EnrollmentRequest? oldRequest = GetEnrollmentRequestById(enrollmentRequest.Id);
             if (oldRequest == null) return null;
 
             oldRequest.Status = enrollmentRequest.Status;
-
+            oldRequest.IsCanceled = enrollmentRequest.IsCanceled;
+            oldRequest.LastModifiedTimestamp = DateTime.Now;
             _repository.Save(_enrollmentRequests);
             NotifyObservers();
             return oldRequest;
@@ -54,7 +57,7 @@ public EnrollmentRequest Add(EnrollmentRequest enrollmentRequest)
 
         public EnrollmentRequest? Remove(int id)
         {
-            EnrollmentRequest enrollmentRequest = GetEnrollmentRequestById(id);
+            EnrollmentRequest? enrollmentRequest = GetEnrollmentRequestById(id);
             if (enrollmentRequest == null) return null; 
 
             _enrollmentRequests.Remove(enrollmentRequest.Id);
@@ -65,13 +68,48 @@ public EnrollmentRequest Add(EnrollmentRequest enrollmentRequest)
 
         public List<EnrollmentRequest> GetStudentRequests(int studentId)
         {
-            Dictionary<int, EnrollmentRequest> studentRequests = new();
-            foreach (EnrollmentRequest enrollmentRequest in GetAllEnrollmentRequests().Values)
+            List<EnrollmentRequest> studentRequests = new();
+            foreach (EnrollmentRequest enrollmentRequest in GetAllEnrollmentRequests())
             {
-                if (enrollmentRequest.StudentId == studentId) studentRequests.Add(enrollmentRequest.Id, enrollmentRequest);
+                if (enrollmentRequest.StudentId == studentId) studentRequests.Add(enrollmentRequest);
+            }
+            return studentRequests;
+        }
+
+        // returns true if the cancellation was successful, otherwise false
+        public bool CancelRequest(EnrollmentRequest enrollmentRequest, Course course)
+        {
+            if (course.StartDateTime.Date - DateTime.Now.Date <= TimeSpan.FromDays(7))
+                return false; // course start date must be at least 7 days away
+
+            enrollmentRequest.IsCanceled = true;
+            return true;
+        }
 
+        public void PauseRequests(int studentId, int acceptedRequestId)
+        {
+            var studentRequests = GetStudentRequests(studentId);
+            foreach (EnrollmentRequest er in studentRequests)
+            {
+                if (er.Id == acceptedRequestId)
+                {
+                    er.UpdateStatus(Status.Accepted);
+                }
+                else if (er.Status == Status.Pending && !er.IsCanceled)
+                {
+                    er.UpdateStatus(Status.Paused);
+                }
             }
-            return studentRequests.Values.ToList();
         }
+
+        public void ResumePausedRequests(int studentId)
+        {
+            var studentRequests = GetStudentRequests(studentId);
+            foreach (EnrollmentRequest request in studentRequests)
+            {
+                if (request.Status == Status.Paused) request.UpdateStatus(Status.Pending);
+            }
+        }
+
     }
 }
diff --git a/LangLang/Core/Model/DAO/StudentDAO.cs b/LangLang/Core/Model/DAO/StudentDAO.cs
index 91f0925e..4228f8e8 100644
--- a/LangLang/Core/Model/DAO/StudentDAO.cs
+++ b/LangLang/Core/Model/DAO/StudentDAO.cs
@@ -4,20 +4,16 @@
 using LangLang.Core.Observer;
 using LangLang.Core.Controller;
 using LangLang.Core.Model.Enums;
+using System;
 
 namespace LangLang.Core.Model.DAO
 {
-    /**
-     * This class encapsulates a list of Student objects and provides methods
-     * for adding, updating, deleting, and retrieving Student objects.
-     * Additionally, this class uses Repository<Student> for loading and saving objects.
-    **/
     public class StudentDAO : Subject
     {
         private readonly Dictionary<int, Student> _students;
         private readonly Repository<Student> _repository;
-    
-    
+
+
         public StudentDAO()
         {
             _repository = new Repository<Student>("students.csv");
@@ -69,7 +65,7 @@ public Student AddStudent(Student student)
             NotifyObservers();
             return oldStudent;
         }
-     
+
         public Student? RemoveStudent(int id, EnrollmentRequestController enrollmentRequestController)
         {
             Student student = GetStudentById(id);
@@ -130,15 +126,28 @@ public List<ExamSlot> GetAvailableExamSlots(Student student, CourseController co
             return availableExamSlots;
         }
 
-        public bool CanModifyInfo(int studentId, EnrollmentRequestController erc)
+        public bool CanModifyInfo(int studentId, EnrollmentRequestController erController, CourseController courseController)
         {
-            List<EnrollmentRequest> studentRequests = erc.GetStudentRequests(studentId);
-            foreach (EnrollmentRequest request in studentRequests)
-            {
-                if (request.Status == Status.Accepted) return false; // TODO: Check if the course is incomplete upon implementing functionality in courseController.
+            // can modify - student is not currently enrolled in any course and has not applied for any exams
+            return (CanRequestEnroll(studentId, erController, courseController) && !HasRegisteredForExam());
+        }
 
+        public bool CanRequestEnroll(int id, EnrollmentRequestController erController, CourseController courseController)
+        {
+            foreach (EnrollmentRequest er in erController.GetStudentRequests(id))
+            {
+                if (er.Status == Status.Accepted && !er.IsCanceled)
+                {
+                    if (!courseController.IsCompleted(er.Id)) return false;
+                }
             }
             return true;
         }
+
+        public bool HasRegisteredForExam()
+        {
+            // TODO: Implement this method once the exam application class is implemented.
+            return false;
+        }
     }
 }
diff --git a/LangLang/Core/Model/EnrollmentRequest.cs b/LangLang/Core/Model/EnrollmentRequest.cs
index bb80c700..f09f0f4b 100644
--- a/LangLang/Core/Model/EnrollmentRequest.cs
+++ b/LangLang/Core/Model/EnrollmentRequest.cs
@@ -9,19 +9,28 @@ public class EnrollmentRequest : ISerializable
         public int Id { get; set; }
         public int StudentId { get; set; }
         public int CourseId { get; set; }
-        public Status Status { get; set; }
+        public Status Status { get; private set; }
         public DateTime RequestSentAt { get; set; }
         public DateTime LastModifiedTimestamp { get; set; }
+        public bool IsCanceled { get; set; }
 
         public EnrollmentRequest() { }
 
-        public EnrollmentRequest(int id, int studentId, int courseId, Status erStatus, DateTime requestSentAt)
+        public EnrollmentRequest(int id, int studentId, int courseId, Status status, DateTime requestSentAt)
         {
             Id = id;
             StudentId = studentId;
             CourseId = courseId;
-            Status = erStatus;
+            Status = status;
             RequestSentAt = requestSentAt;
+            LastModifiedTimestamp = requestSentAt; //Later this will refer to the date of acceptance/rejection/cancellation
+            IsCanceled = false; // this refers whether the student has canceled request before the course has started  
+        }
+
+        public void UpdateStatus(Status status)
+        {
+            Status = status;
+            LastModifiedTimestamp = DateTime.Now;
         }
 
         public void FromCSV(string[] values)
@@ -38,6 +47,7 @@ public void FromCSV(string[] values)
             StudentId = int.Parse(values[1]);
             CourseId = int.Parse(values[2]);
             Status = (Status)Enum.Parse(typeof(Status), values[3]);
+            IsCanceled = bool.Parse(values[6]);
         }
 
         public string[] ToCSV()
@@ -48,7 +58,8 @@ public string[] ToCSV()
                 CourseId.ToString(),
                 Status.ToString(),
                 RequestSentAt.ToString("yyyy-MM-dd"),
-                LastModifiedTimestamp.ToString("yyyy-MM-dd")
+                LastModifiedTimestamp.ToString("yyyy-MM-dd"),
+                IsCanceled.ToString()
             };
         }
     }
diff --git a/LangLang/Core/Model/Enums/Status.cs b/LangLang/Core/Model/Enums/Status.cs
index d511cbc6..4478fac5 100644
--- a/LangLang/Core/Model/Enums/Status.cs
+++ b/LangLang/Core/Model/Enums/Status.cs
@@ -5,6 +5,7 @@ public enum Status
     {
         Pending,
         Accepted,
-        Rejected
+        Rejected,
+        Paused
     }
 }
diff --git a/LangLang/Data/enrollmentRequests.csv b/LangLang/Data/enrollmentRequests.csv
index 7ada731c..3f86d48b 100644
--- a/LangLang/Data/enrollmentRequests.csv
+++ b/LangLang/Data/enrollmentRequests.csv
@@ -1,6 +1,6 @@
-0|0|2|Accepted|2024-03-20|2024-03-20
-1|2|0|Accepted|2024-03-10|2024-03-10
-2|0|1|Accepted|2024-02-02|2024-02-02
-3|1|2|Accepted|2024-02-05|2024-02-05
-4|0|0|Accepted|2024-07-07|2024-07-07
-5|0|3|Accepted|2024-08-07|2024-08-07
\ No newline at end of file
+0|0|2|Pending|2024-03-20|2024-03-20|false
+1|2|0|Accepted|2024-03-10|2024-03-10|false
+2|0|1|Pending|2024-02-02|2024-02-02|false
+3|1|2|Accepted|2024-02-05|2024-02-05|false
+4|0|0|Pending|2024-07-07|2024-07-07|false
+5|0|3|Pending|2024-08-07|2024-08-07|false
\ No newline at end of file
diff --git a/LangLang/Data/students.csv b/LangLang/Data/students.csv
index 339a3e04..edfc2d37 100644
--- a/LangLang/Data/students.csv
+++ b/LangLang/Data/students.csv
@@ -1,3 +1,3 @@
-0|Novak|Djokovic|Male|1980-01-01|+36245621|djokovic1@gmail.com|tenis123|Student|tenis player
+0|Novak|Djokovic|Male|1980-01-01|+36245621|nole@gmail.com|idemoo10|Student|tenis player
 1|Nikola|Jokic|Male|1980-01-01|+36245621|jokic1@gmail.com|sombor15|Student|basketball player
 2|Bogdan|Bogdanovic|Male|1998-05-08|+3816532598|bodan@gmail.com|partizan10|Student|basketball player
diff --git a/LangLang/View/StudentGUI/StudentWindow.xaml.cs b/LangLang/View/StudentGUI/StudentWindow.xaml.cs
index 086e322f..7349ef90 100644
--- a/LangLang/View/StudentGUI/StudentWindow.xaml.cs
+++ b/LangLang/View/StudentGUI/StudentWindow.xaml.cs
@@ -143,7 +143,7 @@ private void signoutbtn_Click(object sender, RoutedEventArgs e)
 
         private void editbtn_Click(object sender, RoutedEventArgs e)
         {
-            if (studentController.CanModifyInfo(currentlyLoggedIn.Id, enrollmentRequestController))
+            if (studentController.CanModifyInfo(currentlyLoggedIn.Id, enrollmentRequestController, courseController))
             {
                 EnableAll();
                 EditMode();

From 428943e26e006fff9b266590019e03b97a693b77 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ana=20=C5=A0inik?= <sinikana7@gmail.com>
Date: Mon, 29 Apr 2024 11:58:58 +0200
Subject: [PATCH 6/9] [fix] EnrollmentRequest Update method

---
 LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs b/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs
index 403bb8eb..725d1e73 100644
--- a/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs
+++ b/LangLang/Core/Model/DAO/EnrollmentRequestDAO.cs
@@ -47,7 +47,7 @@ public EnrollmentRequest Add(EnrollmentRequest enrollmentRequest)
             EnrollmentRequest? oldRequest = GetEnrollmentRequestById(enrollmentRequest.Id);
             if (oldRequest == null) return null;
 
-            oldRequest.Status = enrollmentRequest.Status;
+            oldRequest.UpdateStatus(enrollmentRequest.Status);
             oldRequest.IsCanceled = enrollmentRequest.IsCanceled;
             oldRequest.LastModifiedTimestamp = DateTime.Now;
             _repository.Save(_enrollmentRequests);

From 03073577f0be1690c293595e2d1dd7321ba00832 Mon Sep 17 00:00:00 2001
From: Natasa Kasikovic~ <nkasikovic@yahoo.com>
Date: Mon, 29 Apr 2024 12:26:42 +0200
Subject: [PATCH 7/9] [Refactor] remove unused imports and functions

---
 LangLang/DTO/ExamSlotDTO.cs | 46 ++-----------------------------------
 1 file changed, 2 insertions(+), 44 deletions(-)

diff --git a/LangLang/DTO/ExamSlotDTO.cs b/LangLang/DTO/ExamSlotDTO.cs
index 1c134cbc..1bd42f28 100644
--- a/LangLang/DTO/ExamSlotDTO.cs
+++ b/LangLang/DTO/ExamSlotDTO.cs
@@ -1,19 +1,13 @@
 using LangLang.Core.Model;
 using System;
-using System.Collections.Generic;
 using System.ComponentModel;
-using System.Data;
 using System.Diagnostics;
-using System.Linq;
-using System.Reflection;
-using System.Text;
 using System.Text.RegularExpressions;
-using System.Threading.Tasks;
-using System.Xml.Linq;
+
 
 namespace LangLang.DTO
 {
-    public class ExamSlotDTO : INotifyPropertyChanged, IDataErrorInfo
+    public class ExamSlotDTO : INotifyPropertyChanged
     {
         public ExamSlotDTO() {
             _courseId = -1;
@@ -190,40 +184,6 @@ public ExamSlotDTO(ExamSlot examSlot, Course course)
             this.ExamDateTime = examSlot.ExamDateTime;
         }
 
-        private DateTime ToDateTime(DateTime date, string time)
-        {
-
-            string[] timeComponents = time.Split(':');
-
-            if (timeComponents.Length == 2)
-            {
-                // Parse hour component
-                if (int.TryParse(timeComponents[0], out int hours))
-                {
-                    // Parse minute component
-                    if (int.TryParse(timeComponents[1], out int minutes))
-                    {
-                        // Create a new DateTime object with the combined date and time components
-                        DateTime combinedDateTime = new DateTime(date.Year, date.Month, date.Day, hours, minutes, 0);
-
-                    }
-                    else
-                    {
-                        Console.WriteLine("Invalid minute component.");
-                    }
-                }
-                else
-                {
-                    Console.WriteLine("Invalid hour component.");
-                }
-            }
-            else
-            {
-                Console.WriteLine("Invalid time format.");
-            }
-            return DateTime.Now;
-        }
-
         public ExamSlot ToExamSlot()
         {
             string[] timeParts = _time.Split(':');
@@ -232,8 +192,6 @@ public ExamSlot ToExamSlot()
             return new ExamSlot(Id, _courseId, _maxStudents, new DateTime(_examDate.Year, _examDate.Month, _examDate.Day, hour, minute, 0), 0);
         }
 
-        public string Error => throw new NotImplementedException();
-
         public event PropertyChangedEventHandler? PropertyChanged;
 
         protected virtual void OnPropertyChanged(string name)

From cfa72b528c03cd0f69d43d3e09c0009768c708a6 Mon Sep 17 00:00:00 2001
From: DusicaPesic <130140285+DusicaPesic@users.noreply.github.com>
Date: Mon, 29 Apr 2024 13:44:37 +0200
Subject: [PATCH 8/9] [UPDATE] ExamSlotDTO class

Adjusted ExamSlotDTO class to work with new class attributes.
---
 LangLang/Core/Model/TimeSlot.cs |  8 +++++-
 LangLang/DTO/ExamSlotDTO.cs     | 44 ++++++++++++++++++++-------------
 2 files changed, 34 insertions(+), 18 deletions(-)

diff --git a/LangLang/Core/Model/TimeSlot.cs b/LangLang/Core/Model/TimeSlot.cs
index 2073b029..1dd1aad0 100644
--- a/LangLang/Core/Model/TimeSlot.cs
+++ b/LangLang/Core/Model/TimeSlot.cs
@@ -7,7 +7,13 @@ public class TimeSlot
     {
         // NOTE: Adapt as needed during implementation
         public int Duration { get; set; }
-        public DateTime time { get; set; }
+        public DateTime Time { get; set; }
+
+        public TimeSlot(int duration, DateTime time)
+        {
+            Duration = duration;
+            Time = time;
+        }
 
         public bool OverlappsWith(TimeSlot timeSlot)
         {
diff --git a/LangLang/DTO/ExamSlotDTO.cs b/LangLang/DTO/ExamSlotDTO.cs
index 1bd42f28..b636d58e 100644
--- a/LangLang/DTO/ExamSlotDTO.cs
+++ b/LangLang/DTO/ExamSlotDTO.cs
@@ -9,12 +9,10 @@ namespace LangLang.DTO
 {
     public class ExamSlotDTO : INotifyPropertyChanged
     {
-        public ExamSlotDTO() {
-            _courseId = -1;
-        }
+        
         public int Id { get; set; }
 
-        private int _courseId;
+        private int _tutorId;
         private string _language;
         private LanguageLevel _level;
         private int _maxStudents;
@@ -22,14 +20,15 @@ public ExamSlotDTO() {
         private string _time;
         private int _numberOfStudents;
         private DateTime _examDateTime;
+        private bool _applicationPossible;
 
-        public int CourseId
+        public int TutorId
         {
-            get { return _courseId; }
+            get { return _tutorId; }
             set
             {
-                _courseId = value;
-                OnPropertyChanged("CourseId");
+                _tutorId = value;
+                OnPropertyChanged("TutorId");
             }
         }
 
@@ -117,6 +116,16 @@ public DateTime ExamDateTime
             }
         }
 
+        public bool ApplicationPossible
+        {
+            get { return _applicationPossible; }
+            set
+            {
+                _applicationPossible = value;
+                OnPropertyChanged("ApplicationPossible");
+            }
+        }
+
         private readonly Regex _TimeRegex = new("^(?:[01]\\d|2[0-3]):(?:[0-5]\\d)$");
 
 
@@ -171,17 +180,18 @@ public bool IsValid
 
 
 
-        public ExamSlotDTO(ExamSlot examSlot, Course course)
+        public ExamSlotDTO(ExamSlot examSlot, LanguageLevel level, string language, int tutorId, int numberOfStudents)
         {
             this.Id = examSlot.Id;
-            this.Language = course.Language;
-            this.Level = course.Level;
+            this.Language = language;
+            this.Level = level;
+            this.TutorId = tutorId;
             this.MaxStudents = examSlot.MaxStudents.ToString();
-            this.NumberOfStudents = examSlot.NumberOfStudents;
-            this.CourseId = examSlot.CourseId;
-            this.ExamDate = examSlot.ExamDateTime.Date;
-            this.Time = examSlot.ExamDateTime.ToString("HH:mm");
-            this.ExamDateTime = examSlot.ExamDateTime;
+            this.NumberOfStudents = numberOfStudents;
+            this.ExamDate = examSlot.TimeSlot.Time.Date;
+            this.Time = examSlot.TimeSlot.Time.ToString("HH:mm");
+            this.ExamDateTime = examSlot.TimeSlot.Time;
+            this.ApplicationPossible = examSlot.ApplicationPossible;
         }
 
         public ExamSlot ToExamSlot()
@@ -189,7 +199,7 @@ public ExamSlot ToExamSlot()
             string[] timeParts = _time.Split(':');
             int hour = int.Parse(timeParts[0]);
             int minute = int.Parse(timeParts[1]);
-            return new ExamSlot(Id, _courseId, _maxStudents, new DateTime(_examDate.Year, _examDate.Month, _examDate.Day, hour, minute, 0), 0);
+            return new ExamSlot(Id, _language,_level, new TimeSlot(4,new DateTime(_examDate.Year, _examDate.Month, _examDate.Day, hour, minute, 0)), 0,_tutorId,_applicationPossible);
         }
 
         public event PropertyChangedEventHandler? PropertyChanged;

From 25798476fbfc970f602e6f3693ed5afa58311f5d Mon Sep 17 00:00:00 2001
From: DusicaPesic <130140285+DusicaPesic@users.noreply.github.com>
Date: Mon, 29 Apr 2024 14:01:57 +0200
Subject: [PATCH 9/9] [UPDATE] ExamSlotDTO

---
 LangLang/DTO/ExamSlotDTO.cs | 29 +++++++++--------------------
 1 file changed, 9 insertions(+), 20 deletions(-)

diff --git a/LangLang/DTO/ExamSlotDTO.cs b/LangLang/DTO/ExamSlotDTO.cs
index b636d58e..bdb24bef 100644
--- a/LangLang/DTO/ExamSlotDTO.cs
+++ b/LangLang/DTO/ExamSlotDTO.cs
@@ -18,8 +18,7 @@ public class ExamSlotDTO : INotifyPropertyChanged
         private int _maxStudents;
         private DateTime _examDate;
         private string _time;
-        private int _numberOfStudents;
-        private DateTime _examDateTime;
+        private int _numberStudents;
         private bool _applicationPossible;
 
         public int TutorId
@@ -67,7 +66,7 @@ public string MaxStudents
                 if (int.TryParse(value, out int result) && result >= 0)
                 {
                     _maxStudents = result;
-                    //OnPropertyChanged("MaxStudents");
+                    OnPropertyChanged("MaxStudents");
                 }
                 else
                 {
@@ -87,13 +86,13 @@ public DateTime ExamDate
             }
         }
 
-        public int NumberOfStudents
+        public int NumberStudents
         {
-            get { return _numberOfStudents; }
+            get { return _numberStudents; }
             set
             {
-                _numberOfStudents = value;
-                //OnPropertyChanged("NumberOfStudents");
+                _numberStudents = value;
+                OnPropertyChanged("NumberOfStudents");
             }
         }
 
@@ -107,14 +106,6 @@ public string Time
             }
         }
 
-        public DateTime ExamDateTime
-        {
-            get { return _examDateTime; }
-            set 
-            {
-                _examDateTime = value;
-            }
-        }
 
         public bool ApplicationPossible
         {
@@ -122,7 +113,6 @@ public bool ApplicationPossible
             set
             {
                 _applicationPossible = value;
-                OnPropertyChanged("ApplicationPossible");
             }
         }
 
@@ -180,17 +170,16 @@ public bool IsValid
 
 
 
-        public ExamSlotDTO(ExamSlot examSlot, LanguageLevel level, string language, int tutorId, int numberOfStudents)
+        public ExamSlotDTO(ExamSlot examSlot, LanguageLevel level, string language, int tutorId, int numberStudents)
         {
             this.Id = examSlot.Id;
             this.Language = language;
             this.Level = level;
             this.TutorId = tutorId;
             this.MaxStudents = examSlot.MaxStudents.ToString();
-            this.NumberOfStudents = numberOfStudents;
+            this.NumberStudents = numberStudents;
             this.ExamDate = examSlot.TimeSlot.Time.Date;
             this.Time = examSlot.TimeSlot.Time.ToString("HH:mm");
-            this.ExamDateTime = examSlot.TimeSlot.Time;
             this.ApplicationPossible = examSlot.ApplicationPossible;
         }
 
@@ -199,7 +188,7 @@ public ExamSlot ToExamSlot()
             string[] timeParts = _time.Split(':');
             int hour = int.Parse(timeParts[0]);
             int minute = int.Parse(timeParts[1]);
-            return new ExamSlot(Id, _language,_level, new TimeSlot(4,new DateTime(_examDate.Year, _examDate.Month, _examDate.Day, hour, minute, 0)), 0,_tutorId,_applicationPossible);
+            return new ExamSlot(Id, _language,_level, new TimeSlot(4,new DateTime(_examDate.Year, _examDate.Month, _examDate.Day, hour, minute, 0)),_maxStudents,_tutorId,_applicationPossible);
         }
 
         public event PropertyChangedEventHandler? PropertyChanged;